Higher performance, lower cost, increased miniaturization of integrated circuit components, and greater packaging density of integrated circuits are ongoing goals of the computer industry. As these goals are achieved, microelectronic dice become smaller. Accordingly, the density of power consumption of the integrated circuit components in the microelectronic die has increased, which, in turn, increases the power requirements of other board level components that may be associated with the microelectronic die, such as voltage regulators, which may perform power delivery, for example. If the temperature of these associated components becomes too high, the components may be damaged or destroyed.
Various apparatus and techniques have been used and are presently being used for removing heat from microelectronic dice. One such heat dissipation technique involves the attachment of a high surface area heat sink to a microelectronic die. FIG. 6 illustrates an assembly 200 comprising a microelectronic die 202 (illustrated as a flip chip) physically and electrically attached to a substrate carrier 204 by a plurality of solder balls 206. A heat sink 208 is attached to a back surface 212 of the microelectronic die 202 by a thermally conductive adhesive 214. The heat sink 208 is usually constructed from a thermally conductive material, such as copper, copper alloys, aluminum, aluminum alloys, or any suitable combination thereof. The heat generated by the microelectronic die 202 is drawn into the heat sink 208 (following the path of least thermal resistance) by conductive heat transfer.
High surface area heat sinks 208 are generally used because the rate at which heat is dissipated from a heat sink is substantially proportional to the surface area of the heat sink. The high surface area heat sink 208 usually includes a plurality of projections 216 extending substantially perpendicularly from the microelectronic die 202. It is, of course, understood that the projections 216 may include, but are not limited to, elongate planar fin-like structures and columnar/pillar structures. The high surface area of the projections 216 allows heat to be convectively dissipated from the projections 216 into the air surrounding the high surface area heat sink 208. A fan 218 may be incorporated into the assembly 200 to enhance the convective heat dissipation. However, although high surface area heat sinks are utilized in a variety of microelectronic applications, they may not provide heat dissipation for associated components that may be attached to the substrate carrier 204 (not shown). Additionally, heat sinks such as this may reduce or block airflow to components on a substrate, thereby causing areas of air stagnation, which may result in inadequate heat dissipation for one or more of these components.
Therefore, it would be advantageous to develop apparatus and techniques to effectively remove heat from a microelectronic die while providing some capability for heat dissipation for other components associated with the die.